Durvasa

Durvasa was actually Lord Sankara who was born as the third son to sage Atri and his wife Anasuya. He was known to grant boons and heap curses. When Rama was in conversation with Kalapurusha and had asked Lakshmana not to allow anyone in, Durvasa forced himself inside threatening to curse that Ayodhya and the entire clan would perish. Upon Bhagawan Rudra's intervention, Durvasa agreed to be a ritwik at the yaga of emperor Swethaki. Princess Pritha( Kunti) served the sage with such great devotion and patience that he blessed her with a manthra.When she chanted the manthra with a particular God in mind, the God would grant her desire to her.  Durvasa was held in high esteem by the devas and was an invitee at Lord Brahma's court. Sage Mudgala was a precious gem who was put to a rigorous test by the sage so that his good qualities came out shining. Duryodhana got an opportunity to serve the sage , which he did excellently. He then sent him to the Pandavas hoping to put them in trouble. But, Lord Krishna came to the Pandavas' rescue. Durvasa brought out the utter devotion of Ambareesha towards Lord Vishnu only after putting him through a very difficult test. Even Devendra was not spared from his anger. In fact, he lost all his wealth as a result of the sage's curse. He had to pray hard to Goddess Lakshmi who restored to him all that he had lost. Sri Krishna had great respect for Durvasa. The Yamuna river made way for the Gopikas to  cross so that they could have the sage's darshan and an opportunity to serve him. As they had carried a lot of sweets and other food for Durvasa,the sage who lived on the juice of the 'durve' asked them to put only a little of whatever food they had brought to offer him.But, they were stunned to see that their vessels had become empty!  Once, when Durvasa did tapas in Kashi, the Gods were not pleased and hence did not appear before him. He got so angry that the fire of his anger reached the sky forcing all the Gods to come down in huge numbers. Finally, it was Lord Sankara who convinced the sage not to curse the holy place (Kashi) as many people found their salvation there.  Durvasa dealt with people rather harshly. Ironically, however, it was through his curses that people's virtues came to the fore. So, directly or indirectly, he was responsible for unearthing many a great personality and presenting them to the world.